drugs affecting ANS Flashcards
another name for sympathetic nervous system
adrenergic
another name for parasympathetic nervous system
cholinergic
neurotransmitters that affect SNS
epinephrine, norepinephrine & dopamine (catecholamines)
neurotransmitters that affect Parasymp N System
Ach
Location of nerves/neurons in SNS vs PNS
Sympathetic Nervous System: middle of spinal cord, short neuron first, meets at ganglia, then longer neuron
PNS: long neuron first, then second is shorter
2 types of receptors within ANS
Alpha and Beta receptors (1 & 2)
2 types of receptors within PNS
muscarinic and nicotinic
adrenergic responses of the body: head to toe
pupil dilation, dry mouth, bronchodilation, dec GI motility, inc sweat glands, sphincter contraction to hold pee
cholinergic responses of the body: head to toe
pupil constriction, inc salivation, bronchoconstriction, Inc GI motility, bladder fungus contraction so you can pee
other examples under umbrella term: cholinergic blocking drugs
anti-cholinergic drugs, parasympatholytic, antimuscarinic
Alpha-adrenergic physiological activities: BP, eyes, and GI
Vasoconstriction of arterioles, resulting in higher blood pressure
Pupil dilation
Relaxation of the gut
Beta-adrenergic physiological activities
Cardiac acceleration and increased contractility (inc HR)
Vasodilation of arterioles supplying skeletal muscles
Bronchial relaxation (lungs)
Uterine relaxation
(Adrenergic)
Alpha1 receptors: action
Rx nasal congestion, hypotension
Mediate systemic vasoconstriction
(Adrenergic)
Alpha 2 receptors: what it treats and how
Rx HTN
Inhibit sympathetic vasomotor center and decrease sympathetic outflow to periphery
(Adrenergic)
Beta 1 receptors: what it treats and how
Rx cardiac arrest, heart failure, shock
Mediate increased heart rate, force of contraction, CO
(Adrenergic)
Beta 2 receptors: what it treats and how
Rx asthma, premature labor contractions
Mediate bronchodilation and pupil dilation
this type of drug: Slow heart rate and cause vasodilatation by working centrally in the brain. give examples of it
Alpha 2 receptors
Clonidine (Catapres) and Methyldopa (aldomet)
CLonidine uses
decrease BP
withdrawal symptoms
used for ADHD
Methyldopa uses
treats HTN in pregnant women
can cause hepatotoxicity, hypersensitivity reaction (rash fatigue, etc)
Beta 2 main use:
bronchodilation
alpha blockers (antagonist): action and what it treats
Action: block alpha receptors leading to vasodilation
Used to treat HTN, benign prostatic hyperplasia (BPH), Raynaud’s disease, and migraine headaches
beta blockers
Action: antagonize or block the effects of catecholamines
Can be “selective” to beta1 receptors (heart) or “nonselective” to beta1 receptors
Mainly used for HTN and after myocardial infarction (MI)
drug examples of alpha blockers, risk and ADRs
Prazosin (minipress) and Doxazocin (Cardura)
Doxazosin risk for early HF; both have risk for first dose orthostatic hypotension
another ex of alpha blockers, besides minidress and cardura; used for what and ADRs
Flomax (Tamsulosin)- Have increased selectivity for alpha receptors in prostate
Used for BPH
ADRs: Increased risk of ejaculatory dysfunction
beta blockers that are non-selective
propanolol (crosses blood brain barrier, so good for tremors and migraines), nadolol
ADRs of beta blockers
hypotension, bradycardia, drowsiness, masks hypoglycemia, impotence, dec libido
rational drug selection for choosing beta blockers:
works well in African Americans; ace inhibitors don’t work well on them
education on beta blocker use:
abrupt withdrawal can cause reflect tachycardia; life-threatening
drug examples of combined alpha and beta blockers
carvidolol (coreg) and labetolol (normodyne);
treats HTN and slows progression of HF
cholinergic agents can be what two classifications:
direct acting or indirect acting
drug prototypes for direct acting cholinergic drugs
bethanicol and Pilocarpine
drug prototypes for indirect acting cholinergic drugs
neostigmine bromide (Prostigmin)
main uses of cholinergic drugs
To decrease intraocular pressure in glaucoma (bc PNS constricts pupils)
To treat atony of gastrointestinal tract and urinary bladder (bc PNS ups GI system; ex:give post-op tp help them move food and pee)
To diagnose and treat myasthenia gravis (not enough Ach)
this drug treats anticholinergic toxicity
physostigmine
Betanechol
direct acting cholinergic drug
Increases tone of detrusor muscle and causes bladder contractions Increases gastric tone ADRs – rare if given po Clinical use Neurogenic bladder atony
examples of anti-cholinergic drugs
atropine- for severe bradycardia
scopolamine- motion sickness
Artane and cogentin- treats tremors, salivation, and EPA symptoms in EPS
oxybutinin (ditropan) treats overactive bladder
dicyclomine (bentyl) treats IBD
Ipatroprium Bromide- bronchodilator
what are ADRs of anticholinergic drugs
tachycardia, dry oral and resp. secretions, and constipation
examples of indirect acting cholinergic drugs
cholinesterase inhibitors:
- Neostigmine and Pyridostigmine- intensifies effects of Ash –> treatment for M gravis
- Donezepil (aricept)- treats alzhiemers’s (prevents degradation of Ach by blocking AChe
